Static push-out tests and finite element studies on larger diameter shear studs for composite steel bridges

Efficient steel bridge girder design makes use of composite action between the concrete bridge deck and the steel girders. The critical link between the deck and the girders are shear studs welded to the girder top flange. The most commonly used shear studs have a 7/8-inch diameter and are welded to the top flange of the beam in a fabrication shop or in the field. A very large number of shear studs is typically needed to satisfy AASHTO fatigue requirements. The large number of shear studs on beams makes the placement of partial depth precast concrete deck panels difficult. The large number of shear studs also create a safety hazard for workers during erection and early stages of construction due to limited space to walk on the flange. Using larger diameter shear studs can significantly reduce the number of studs required on composite steel girders, thereby enhancing construction safety and facilitating the increased use of precast deck panels on steel bridges. This dissertation is part of a larger research project examining the feasibility of using shear stud diameters greater than 7/8-inch for composite steel bridge construction, and the development of design guidelines for evaluating the static and fatigue strength of larger diameter shear studs. Shear stud diameters up to 1-1/4 inch were considered in the research project. The focus of this dissertation is two major contributions to the larger research project described above. These two contributions are conducting an extensive series of push-out tests and conducting detailed finite element studies of the behavior of shear studs embedded in concrete bridge decks. An extensive series of push-out tests were conducted to collect experimental data on the static loading behavior of larger diameter shears studs. These tests focused on 1-1/8-inch diameter studs, but also included tests on 7/8-inch dimeter studs for baseline comparisons. The static push-out tests generated data on load-slip behavior of the studs to characterize the stiffness, strength, and slip capacity of the studs. The tests explored a number of variables, including stud layout, deck reinforcing details, and stud penetration into concrete deck. Tests were conducted on full-depth cast-in-place decks as well as decks constructed using partial depth precast concrete panels. This dissertation also includes finite element analysis (FEA) of the local behavior of shear studs embedded in a concrete bridge deck. The commercially available FEA package Abaqus was used for this task. A variety of modeling approaches were explored, and the push-out test results were used for assessing model performance and accuracy. The load-slip response and failure modes of the test specimens were compared with model predictions. Once validated modeling approaches are established, parametric studies were done to further explore design variables not included in the experimental push-out tests.

Name thesis:degree_name

Doctor of Philosophy

Level thesis:degree_level

Doctoral

Grantor

The University of Texas at Austin

Year dc:date.issued

2023

Author dc:creator

• Deng, Xianjue

Advisors dc:contributor.advisor

• Engelhardt, Michael D.
• Helwig, Todd Aaron, 1965-

Committee members dc:contributor.committeemember

• Koutromanos, Ioannis
• Williamson, Eric B

• Finite element method
• Push-out test
• Larger diameter shear stud
• Steel bridge

Language dc:language.iso

en

Identifier URI

https://doi.org/10.26153/tsw/59175

OAI identifier oai:identifier

oai:repositories.lib.utexas.edu:2152/131831